Cramp



S. C. BOADLE Aprll 6 1926;

CRAMP Filed Sept. 12, 1925 Jive 7L'Z'0 7* gym Patented Apr. 6, 1926.

I UNITED, STATES;

" anemi Application filed September 12, 1925.; Seriall No. 55,914.

To allwhom it may concern. I 1

a subj ect: of the King. of Great Britain, re-

siding at 79 Bayswater Road, Kensington,

inthe State of'victoria,Commonwealth of Australia, has invented. certain new I and useful Improvements in and Relating to cation. Y

This inventionhasbeen devised to provide improvements in and relating to tramps, vises. or the like mechanism, and is particularly useful for; holding, individual Cramps, of which the following isa specifiobjects such. for instance as metalrplates, and the invention will be described herein in reference thereto, but itris to be understood thattheuse of the invention: is not limited thereto, as it may: be employed wherever it is desired to grip. and hold any particular object or obj ectsfor the purposes required. H

The o-bjects' ofthe invention ,are many, one of which is tqprovide a cramp, the

i 1 parts of which areconstruc'tedzand arranged to enable a. maximum. of gripping force to vbe obtained by a minimum of adjusting force, and that the 'grippinglforce is applied at theopposite endto that of-the adjusting a force and at the'other end of the instrument. .1

Another object of this. 'inventionis to provide a cramp, thejaws of which can be broughtftotlie. gripping position at any point in their moving area with a minimum travel of the adjusting screw bolt.

Another object of this invention is to pro-vide a cramp, the jaws of which-are shaped to enable at whatever positionthe'y I are set, the gripping or biting position thereof will be placed to take the stress at the strongest pointjof each jaw.

A. further object .of this spring pawl to enable the adjusting force to be transferred to a grippingforce.

V In order that my invention may be the more easily understood, reference will be made to the accompanying sheet-of drawin 's in whichiig 1 is a side elevation of thecramp constructed according to my invention.

Fig. 2 is a plan view of Fig. 1 whilste Fig. 3 is a part sectional elevation of Fig.

invention is to provide a cramp in which one of the jaws. is loose on a bearing pin, and has at its inner end a ratchet, being controlled by a f p" l 'illustrating thejawsset ata differentpo- Be it known that SIDNEY CHARLES BOADLE, V I i sition.

I provide an. elongated member 1 of thedesired dimensions to ensure thenecessary strength to meet the inherent stresses and-v strains tov which it will be subjected.

Thememberl has at one end a curved aw 3, called the fixed jaw, the serrated end 4 1 of. which is curved and forms a gripping;

or biting-:face. The member '1 is provided, betweeni ts. ends, with a fork; the divisions of which are'preferably formed by spaced apart ears 2, 2,1integral withthe member. The fork; ears 2 have-orifices 'receivingthe' ends of 'apin 5, uponwhich ismounted a. bifurcated lever, 6, interposed between the earsj2 and'extending substantially parallel with theme nber 1." The outer end of the,

lever6 has atapped orifice engaged with a;

screw bolt 7, bearingon-the meinber 1, and;

a purpose hereinafter stated.

I Mounted on the pin 5, between. the' div i- .sionspf .the;b1furcated;lever 6,.is a curved.

swinging aw 9, having acurved serrated gr pp ng face 4, opposed to, the face 1.

o The inner or, hub portion ofthe; swinging jaw, 9, and the lever 6, are provided with.

means for holding the s'wingingjaw invarious positions relative to the lever, and peradapted to exertpressureon the lev en fori mitting a quick adjusting movement of the jaw toward and from; theafixed jaw, said A member is a pawl 11, fixed to a pin 13, which is adapted to'turn in bearings formed in the divisions of the bifurcated lever 6, the

ratchet and pawl being between saiddivisions. The pawl is. preferably held yieldinglyin engagement with the ratchet by a spring 12, and may be disengaged from the ratchet by a handle or trigger 14, fixed to the pin 13. e

The screw 7 constitutes a means for exerting pressure on the lever 6, to cause the lat- I ter to exert gripping force on the swinging jaw 9, through the clutch.

Before use the parts may be adjusted as shown by Figure 1, the gripping faces being closed on each other, or nearly so. The pawl is then released fromthe ratchet, the swinging jaw '9-is moved outward from the fixed jaw, to. permit the application of the jaws to the object to be gripped, and the pawl is allowed to again engage the ratchet. The screw 7 is now turned inward and exerts gripping pressure on the upper jaw through the lever 6, the pawl and the ratchet. The releasing operation is performed by turning the screw 7 outward until the swinging aw releases the object.

The member 1 may be provided with a shackle 15, for general hauling purposes.

From the above description of parts and of the operation, it will be seen that minimum adjusting force is only required to provide a maximum gripping force at the contact or biting points of the jaws, and that the loose jaw can be adjusted to be placed in such a position to the object that a minimum travel of the screw bolt causes the lifting pressure of the lever arm to be transferred to the jaws providing a thorough and reliable grip on the object or objects between the jaws.

Furthermore the shape and position of the jaws ensures at whatever angle they are set i. e. gripping that the stresses and strains will be at the strongest point of the jaws.

It will be understood that the integral jaw may be constructed in the same manner as the other jaw, in which instance a second i pawl and ratchet mechanism would be employed.

Claims I 1. A cramp comprising a member having an integral gripping jaw and a fork in which bearings are provided for a pin upon which is mounted a bifurcated lever and a loose gripping jaw with teeth, and means for controlling the movement and placing the grip on such jaws.

2. A cramp comprising a member with integral gripping jaw, a fork in which bearings are provided for' a pin, a bifurcated lever mounted thereon, a loose gripping jaw with teeth, a spring pawl mounted on a movable pin, and disposed within the bifu'rcation of the lever arm, a trigger fixed to said movable pin, a screw bolt at the rear of the lever arm for the purpose of engaging with the member, and serrations at the contact surface of the gripping jaws.

3. A cramp comprising an elongated member having at one end a fixed gripping jaw and between its ends a fork, a swinging gripping jaw pivoted to said fork and adapted to swing toward and from the fixed jaw, a bifurcated lever pivoted to the fork and to the swinging jaw, clutch means 'for holding the swinging jaw in various posi tions relative to the lever, and means for exerting pressure on the lever to cause the latter to exert gripping force on the swinging jaw through said clutch means.

4. A cramp comprising an elongated member having at one end afixed gripping jaw and between its ends a fork, a swinging gripping jaw pivoted to said fork and adapted to swing toward and from the fixed jaw, a bifurcated lever pivoted to the fork and to the swinging jaw, a clutch including a ratchet formed on the swinging jaw, and a pawl pivoted to the lever, said clutch being adapted to variably confine the swinging jaw against movement in one direction relative to the lever and outward from the fixed jaw, and a pressure-exerting screw engaged with a tapped orifice in the lever and bearing on an end portion of the elongated 1nember,'and adapted toexert pressure on the lever to cause the latter to exert gripping force on the swinging jaw through the clutch. r.

In testimony whereof I have signed my name to this specification.

SIDNEY CHARLES BOADLE. 

